Combustion chamber of a gas turbine, gas turbine and method for operating the same

ABSTRACT

A combustion chamber assembly of a gas turbine, for combusting a fuel in the presence of combustion air, includes: a combustion chamber, in which combustion of fuel occurs; a precombustion chamber upstream of the combustion chamber; an atomization device that feeds a liquid fuel to the precombustion chamber; and a swirl body that feeds combustion air and gaseous fuel to the precombustion chamber. The combustion chamber assembly is configured as a dual-fuel combustion chamber assembly, which, in a gas fuel operating mode, feeds a mixture of a gaseous fuel and combustion air to the combustion chamber via the swirl body, and which, in a liquid fuel operating mode, feeds liquid fuel to the combustion chamber via the atomization device and combustion air to the combustion chamber via the swirl body. The atomization device includes an atomization lance with a central atomization nozzle, and plural decentralized atomization nozzles.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The invention relates to a combustion chamber assembly, having a combustion chamber, of a gas turbine, a gas turbine having such a combustion chamber assembly and to a method for operating such a gas turbine.

2. Description of the Related Art

Gas turbines comprise a combustion chamber and a turbine arranged downstream of the combustion chamber. In the combustion chamber of a gas turbine, a fuel is combusted and hot exhaust gas created in the process. The hot exhaust gas is expanded in the turbine of the gas turbine to extract energy in the process, which can serve for providing drive power in order to, for example, drive a generator for generating electric current. Gas turbines designed as dual fuel turbines are already known from practice. Such dual fuel gas turbines comprise a dual fuel combustion chamber in which in a gas fuel operating mode a gaseous fuel and in a liquid fuel operating mode a liquid fuel are combusted. In the gas fuel operating mode, a mixture of a gaseous fuel and combustion air can be fed to the combustion chamber via a swirl body. In the liquid fuel operating mode, the liquid fuel can be fed to the combustion chamber of the gas turbine via an atomization device and the combustion air via the swirl body.

Thus, there is a need for further improving combustion chambers of a gas turbine formed as dual fuel combustion chambers so that, in particular in the liquid fuel operating mode, the liquid fuel can be more effectively combusted, namely while reducing undesirable exhaust gas emissions such as nitrogen oxide emissions.

SUMMARY OF THE INVENTION

Starting out from the above, an object of the present invention is to create a new type of combustion chamber assembly, including a combustion chamber, of a gas turbine, a gas turbine of such a combustion chamber assembly and a method for operating such a gas turbine.

This object may be attained, in one aspect of the invention through a combustion chamber assembly of a gas turbine in which, the atomization device of which comprises, based on a longitudinal center axis of the combustion chamber or based on a longitudinal center axis of a precombustion chamber of the combustion chamber assembly, a central atomization lance with at least one atomization nozzle. The atomization device, furthermore, comprises multiple, based on the longitudinal center axis of the combustion chamber or based on the longitudinal center axis of the precombustion chamber of the combustion chamber assembly, decentralized atomization nozzles.

Via the central atomization lance, which comprises at least one atomization nozzle, and via the multiple decentralized atomization nozzles, the liquid fuel, in the liquid fuel operating mode, can be optimally introduced into the combustion chamber to ensure effective combustion of the liquid fuel. By way of the central atomization lance, the liquid fuel can be directly introduced into a central recirculation zone within the combustion chamber or the precombustion chamber of the combustion chamber assembly, as a result of which a stable combustion can be achieved. Here, introducing the fuel via the central atomization lance does not take place homogeneously to the combustion air, no premixing of liquid fuel and combustion air takes place here. By way of the decentralized atomization nozzles, the liquid fuel can be homogeneously distributed in the combustion air. Furthermore, a part premixing of liquid fuel and combustion air is achieved via the decentralized atomization nozzle. By way of the decentralized atomization nozzles, exhaust gas emissions, in particular nitrogen oxide emissions, can be reduced compared with the central atomization lance.

According to a further development of the invention, the decentralized atomization nozzles are positioned on a circular path extending about the longitudinal center axis of the combustion chamber or about the longitudinal center axis of the precombustion chamber of the combustion chamber assembly. Preferentially, a center point of the circular path on which the decentralized atomization nozzle is positioned, is positioned on the longitudinal center axis of the combustion chamber or the precombustion chamber of the combustion chamber assembly. Preferentially, a radius of the circular path, on which the decentralized atomization nozzles are positioned, preferably amounts to between 0.4 times and 1.1 times and the inner radius of the swirl body. By way of such decentralized atomization nozzles, with fuel, providing a homogenous distribution of the same with the combustion air and with respect to a premixing of the same with the combustion air can be optimally introduced into the combustion chamber in order to reduce exhaust gas emissions such as nitrogen oxide emissions as much as possible.

According to a further development of the invention, the central atomization lance comprises at least two, preferentially two atomization nozzles, which alone and jointly each provide an atomization cone with a maximum spray angle of 60°, preferentially of maximally 55°. Each of the decentralized atomization nozzles provides an atomization cone with a maximum spray angle of 40°, preferentially of maximally 30°. In this manner, it can be avoided that walls of the combustion chamber and of the precombustion chamber are wetted with liquid fuel. In particular, this serves for the effective combustion of the liquid fuel while the reduction of exhaust gas emissions.

According to a further development of the invention, the central atomization lance, while forming a radial gap, is bounded by an adjoining component radially outside, at least in sections, wherein the combustion chamber can be supplied with combustion air via the radial gap while bypassing the swirl body. When using the central atomization lance for introducing the liquid fuel into the combustion chamber or precombustion chamber of the combustion chamber assembly, an effective combustion of the liquid fuel in the liquid fuel operating mode while reducing in particular nitrogen oxide emissions can also be ensured by this.

According to a first version of the method according to an aspect of the invention, both the central atomization lance and also the decentralized atomization nozzles are utilized in the liquid fuel operating mode throughout the operating range between no load and full load in order to feed the liquid fuel to the combustion chamber. This operating version of the invention is suitable in particular when the gas turbine to be operated is to perform rapid load changes since individual injection nozzles then need not be activated or deactivated. Purging procedures, as are required when switching off individual atomization nozzles, can be avoided in this way. Compared with gas turbines, the combustion chambers of which only have a central atomization lance, exhaust gas emissions can be reduced.

According to a second version of the method according to an aspect of the invention, both the central atomization lance and also the decentralized atomization nozzles are utilized in the liquid fuel operating mode in an operating range below a predetermined load limit in order to feed liquid fuel to the combustion chamber, whereas in an operating range above the predetermined load limit exclusively the decentralized atomization nozzles are utilized in order to feed the liquid fuel to the combustion chamber. This operating version of the invention serves for further reducing exhaust gas emissions, in particular nitrogen oxide emissions. In an upper load range, the central atomization lance for introducing the liquid fuel is not utilized further but the introduction of the liquid fuel in the upper load range takes place exclusively using the decentralized atomization nozzles. Because of this, exhaust gas emissions such as nitrogen oxide emissions can be further reduced namely in the operating range of high loads.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred further developments of the invention are obtained from the description. Exemplary embodiments of the invention are explained in more detail by way of the drawings without being restricted to this. In the drawings:

FIG. 1 is a highly schematic extract from a combustion chamber assembly of a gas turbine according to the invention;

FIG. 2 shows the area detail II of FIG. 1;

FIG. 3 is a detail of FIG. 1 in viewing direction III;

FIG. 4 is a diagram for illustrating a first method according to the invention for operating the gas turbine according to the invention; and

FIG. 5 is a diagram for illustrating a second method according to the invention for operating the gas turbine according to the invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

The invention relates to a combustion chamber assembly of a gas turbine, to a gas turbine having such a combustion chamber assembly and to a method for operating such a gas turbine.

FIG. 1 shows a schematic extract from a gas turbine in the region of a combustion chamber 1. The combustion chamber 1 is delimited by a wall 2, wherein in the combustion chamber 1 a fuel is combusted. Exhaust gas generated during the combustion of the fuel in the combustion chamber 1 can be fed to a turbine 100 of the gas turbine in order to expand the exhaust gas in the turbine and extract energy in the process.

The combustion chamber assembly is configured as dual fuel combustion chamber assembly, which, on the one hand, can be operated in a gas fuel operating mode and, on the other hand, can be operated in a liquid fuel operating mode.

In the gas fuel operating mode of the combustion chamber assembly, a gaseous fuel is combusted in the combustion chamber 1, and a mixture of the gaseous fuel and combustion air is fed to the combustion chamber 1, via a precombustion chamber 9 upstream of the combustion chamber 1, via a swirl body 3.

The swirl body 3 is preferentially embodied as radial swirl body and creates a defined swirl of the mixture of combustion air and gaseous fuel entering the precombustion chamber 9 adjacent the combustion chamber 1. The mixture of the gaseous fuel and the combustion air is ignited in the gas fuel operating mode with the help of an electric ignition device, which is not shown.

In the liquid fuel operating mode of the combustion chamber assembly, a liquid fuel is combusted in the combustion chamber 1, and the liquid fuel is fed to the combustion chamber 1, via the precombustion chamber 9, with the help of an atomization device 4.

The atomization device 4 comprises a central atomization lance 17 which is positioned approximately in the middle of the precombustion chamber 9 or on a longitudinal center axis 20 of the precombustion chamber 9 or on a longitudinal center axis 20 of the combustion chamber 1 and injects the liquid fuel in the direction of the longitudinal center axis 20 into the precombustion chamber 9 while forming an atomization cone or spray cone 8 a.

In addition, with respect to the longitudinal center axis 20 of the combustion chamber 1, or of the precombustion chamber 9, central atomization lance 17, the atomization device 4 comprises multiple, based on the longitudinal center axis 20 of the combustion chamber 1, or precombustion chamber 9, decentralized atomization nozzles 18, which can likewise inject the liquid fuel into the precombustion chamber 9, namely while forming a respective spray cone 8 b.

Accordingly, the atomization device 4 comprises the central atomization lance 17 and multiple decentralized atomization nozzles 18. The central atomization lance 17 comprises at least one atomization nozzle, preferentially multiple atomization nozzles 15, 16 (see FIG. 2).

FIG. 2 shows a detail of the central atomization lance 17 of the atomization device 4. Between the atomization lance 17, which is received in an assembly wall 12 of the combustion chamber assembly, and an adjoining component 5, which is likewise received in the assembly wall 12, which follows the atomization lance 17 of the atomization device 4 radially outside and which surrounds the atomization lance 17 of the atomization device 4 radially outside at least in sections, a radial gap 6 is formed via which combustion air can be likewise fed to the precombustion chamber 9, while bypassing the swirl body 3. Accordingly, an arrow 13 (see FIG. 1) visualises a flow of combustion air via the swirl body 3 and an arrow 14 (see FIG. 2) a flow of combustion air via the radial gap 6 between the atomization lance 17 and the component 5, wherein the combustion air flow via this radial gap 6 is conducted via a swirl body 25.

The specific component 5, which together with the atomization lance 17 of the atomization device 4 provides the annular gap 6, is preferentially embodied as a separate sleeve connected to the atomization lance 17. In contrast with this it is also possible that the assembly wall 12 itself defines the component 5 adjoining the atomization lance 17 radially outside, which, together with the atomization lance 17, defines the radial gap 6.

Based on the longitudinal center axis 20 of the combustion chamber 1 or precombustion chamber 9, the decentralized atomization nozzles 8 of the atomization device 4 are preferentially positioned on a circular path 19 (see FIG. 3), which extends about the longitudinal center axis 20 of the combustion chamber 1 or the longitudinal center axis 20 of the precombustion chamber 9.

A center point of this circular path 19, on which the decentralized atomization nozzles 18 are positioned, is positioned on the longitudinal center axis 20 in this case. The decentralized atomization nozzles 18 accordingly surround the central atomization lance 17, preferentially concentrically.

FIG. 3 shows a radius d₁₈ of the circular path 19, on which the decentralized atomization nozzles 18 are arranged. Here it is provided, in particular, that this radius dig of the circular path 19, on which the decentralized atomization nozzles 18 are positioned, amounts to between 0.4 times and 1.11 times an inner diameter d₃ of the swirl body 3. In particular, when the radius d₁₈ of the circular path 19, on which the decentralized atomization nozzles 18 are arranged, amounts to between 1.0 times and 1.1 times the inner diameter d₃ of the swirl body 3 is the swirl body 3 at least partly covered by the decentralized atomization nozzles 18 in its outlet region.

The decentralized atomization nozzles 18 can also be arranged on multiple preferentially concentric circular paths or on an elliptical path or a polygon.

As already explained, the central atomization lance 17 of the atomization device 4 preferentially comprises multiple atomization nozzles, in the exemplary embodiment of FIG. 2, two atomization nozzles 15, 16, which are preferentially swirl atomization nozzles. These two atomization nozzles 15, 16 of the central atomization lance 17 can be supplied with the liquid fuel in the liquid fuel operating mode originating from a common liquid fuel feed 21, wherein the fuel conducted from the liquid fuel feed 21 can be divided into two liquid fuel part feeds 21 a, 21 b in order to supply both atomization nozzles 15, 16 of the central atomization lance 17 with liquid fuel.

The central atomization lance 17 with both its atomization nozzles 15, 16 sprays in the liquid fuel in the direction of the combustion chamber 1 with the spray angle α which maximally amounts to 60°, preferentially maximally 55°. In particular when both atomization nozzles 15, 16 of the atomization lance 17 are jointly operated and also, in particular, when one of these atomization nozzles 15, 16 is operated alone, does the spray angle α amount to maximally 60°, preferentially maximally 55° in each case. Because of this it is ensured that neither walls 2 a of the precombustion chamber 9 nor walls 2 of the combustion chamber 1 are wetted with liquid fuel, as a result of which a more effective combustion of the liquid fuel can be provided.

As already explained, combustion air can be fed via the gap 6 to the combustion chamber 1, via the precombustion chamber 9. The air flow 14 conducted via this annular gap 6 serves, on the one hand, for cooling the central atomization lance 17 of the atomization device 4 while this air flow 14, on the other hand, at least partly surrounds the spray cone 8 a of the liquid fuel of the atomization lance 17 on the outside, thus bundling the same.

The specific combustion air 14, which can be fed to the combustion chamber 1, in FIG. 1, via the precombustion chamber 9, while bypassing the swirl body 3 via the radial gap 6, amounts to in particular between 1% and 10% of the combustion air that can be fed to the combustion chamber via the swirl body 3.

Here, the combustion air flow 14 cannot only be fed to the combustion chamber 1 via the radial gap 6 in the liquid fuel operating mode but can also be fed via the radial gap 6 in the gas fuel operating mode, In the gas fuel operating mode the atomization device 4, i.e., in particular the atomization lance 17 of the same, is inactive so that in the gas fuel operating mode no fuel is then introduced via the atomization device 4, but is only supplied via the swirl body 3.

As already explained, the atomization lance 17 is orientated centrically, with respect to the longitudinal center axis 20; liquid fuel can be introduced into a central recirculation zone via the atomization lance 17 in the liquid fuel operating mode. Because of this, a very stable combustion can be ensured. Introducing the liquid fuel, based on the longitudinal center axis 20, via the central atomization lance 17 accordingly takes place locally, i.e., not homogeneously to the combustion air, so that no premixing of liquid fuel and combustion air takes place.

As already explained, the combustion chamber assembly, in addition to the central atomization lance 17, comprises multiple decentralized atomization nozzles 18, which are preferentially arranged on the circular path 19. These decentralized atomization nozzles 18 can be supplied with liquid fuel via a separate liquid fuel feed 22 (see FIG. 1), wherein the decentralized atomization nozzles 18 introduce the liquid fuel into the precombustion chamber 9 or combustion chamber 1 approximately in the same direction as the central atomization lance 17, however with a spray angle β that is smaller than the spray angle α, wherein the spray angle β of the decentralized atomization nozzles 18 preferentially amounts to maximally 40°, preferably maximally 30°.

By virtue of the decentralized atomization nozzles 18, which are preferentially equally distributed over the circular path 19, the fuel, while forming a homogeneous distribution with the combustion air, is introduced into the combustion chamber 1, via the precombustion chamber 9, while at the same time a part premixing of combustion air and liquid fuel is provided, in particular supported in that the decentralized atomization nozzles 18 are arranged adjacent to the outlet of the swirl body 3. This part premixing can be improved when the radius d₁₈ is greater than the radius d₃. Accordingly, the radius d₁₈ can amount to between 1.0 times and 1.1 times the radius d₃.

Preferentially double-jet nozzles or so-called plane jets are utilized as decentralized atomization nozzles 18. By way of the decentralized atomization nozzles 18 a homogeneous supply of the liquid fuel to the combustion air is achieved and furthermore a part premixing of liquid fuel and combustion air.

In particular when the combustion chamber assembly is to be operated in the gas fuel operating mode is a gas-combustion air mixture fed to the combustion chamber 1 via the swirl body 3.

In the gas fuel operating mode, combustion air can likewise be conducted via the annular gap 6. The combustion air flow 14 conducted via the annular gap 6 is branched off in the region of an air space, of a so-called plenum 10, upstream of the swirl body 3.

Accordingly, FIG. 1 shows an air line 11, via which the combustion air can be branched off the plenum 10, wherein the combustion air 14 branched off the plenum 10 is fed via the air line 11 to an air chamber 7 formed by the wall 12 in order to then, starting out from this air chamber 7, to be introduced into the precombustion chamber 9 via the annular gap 6 formed between the atomization lance 17 of the atomization device 4 and the adjoining component 5.

In particular when the combustion chamber assembly is operated in the liquid fuel operating mode with active atomization device 4 is the liquid fuel fed to the combustion chamber 1 or precombustion chamber 9 via the atomization device 4, combustion air via the swirl body 3 and preferentially via the annular gap 6 between the central atomization lance 17 and the component 5.

In a first advantageous operating mode in the liquid fuel operating mode both the central atomization lance 17 and also the decentralized atomization nozzles 18 of the atomization device 4 are utilized throughout the operating range between no load and full load in order to feed liquid fuel to the combustion chamber 1.

For this first operating condition, multiple curve profiles 21, 22, 23 and 24 are shown over the load L of the gas turbine, the curve profile 21 corresponds to the liquid fuel feed 21 via the central atomization lance 17, wherein the curve profile 22 corresponds to the liquid fuel feed 22 via the decentralized atomization nozzles 18, the curve profile 23 shows the load proportion in the total load L, which can be provided by the combustion of the liquid fuel introduced via the central atomization lance 17, and wherein the curve profile 24 shows the load proportion in the total load L that can be provided by the combustion of the fuel that is introduced into the combustion chamber via the decentralized atomization nozzles 18.

Accordingly, FIG. 4 shows that, in particular when fuel is fed to the combustion chamber 1 over the entire load range between 0% (no load) and 100% (full load) both via the central atomization lance 17 and also via the decentralized atomization nozzles 18, preferentially a constant quantity of liquid fuel is fed to the combustion chamber 1 throughout the operating range between no load (0%) and full load (100%) via the central atomization lance (17) (see curve profile 21). Then, the power modulation is effected by changing the liquid fuel introduced into the combustion chamber 1 via the decentralized atomization nozzles (18) (see curve profile 22) so that with increasing load demand L the load proportion 23 of the central atomization lance 17 compared with the load proportion of the decentralized atomization nozzles 18 decreases or the corresponding load proportion 24 of the decentralized atomization nozzles 18 increases.

According to this operating concept, in which throughout the load range or operating range between no load and full load both the central atomization lance 17 and also the decentralized atomization nozzles 18 are utilized to feed the liquid fuel to the combustion chamber it is provided, in particular, that during the acceleration of the gas turbine of the combustion in the combustion chamber 1 fuel is introduced into the combustion chamber 1 exclusively via one of the two atomization nozzles 15, 16 of the atomization lance 17 and that following the acceleration and following the reaching of a defined rotational speed of the gas turbine both atomization nozzles 15, 16 of the atomization lance 17 are utilized and also to introduce the fuel into the combustion chamber 1 via the atomization lance 17.

As already explained, the fuel quantity provided via the central atomization lance 17 over the entire operating range and thus load range of the gas turbine according to the operating concept of FIG. 4 is constant, the power modulation is exclusively effected by varying the fuel quantity provided via the decentralized atomization nozzles 18. This operating concept is suitable in particular for rapid load changes on the gas turbine since, except for the ignition process, no atomization nozzles will then have to be activated or deactivated. Nor is it required to purge the atomization nozzles after the same have been deactivated. This operating concept serves for a very robust and stable combustion of the liquid fuel. In addition to this, low fuel emissions can be realised, in particular nitrogen oxide emissions of less than 150 vppm based on 15% of oxygen.

FIG. 5 illustrates a second operating concept of the combustion chamber assembly according to the invention or of the gas turbine according to the invention comprising the combustion chamber assembly according to the invention. Accordingly, FIG. 5 shows that the load range L between no load (0%) and full load (100%) is divided into two load ranges namely into a load range between no load (0%) and a limit value (GW) and into a load range between a limit value GW and full load (100%).

According to the second operating concept of FIG. 5 according to the invention, both the central atomization lance 17 and also the decentralized atomization nozzles 18 are utilized in the liquid fuel operating mode in the operating range or load range below the predetermined load limit GW in order to feed liquid fuel to the combustion chamber 1. Here, the fuel quantity (see curve profile 21) introduced via the central atomization lance 17 in this load range is preferentially constant, the power modulation in turn is again effected exclusively by changing the liquid fuel quantity introduced via the decentralized atomization nozzles (18) (see curve profile 22).

In the load range above the defined limit value GW, the central atomization lance 17 is deactivated so that no fuel whatsoever is supplied via the same so that in the upper load range between the load limit GW and full load (100%) liquid fuel is then exclusively fed to the combustion chamber 1 via the decentralized atomization nozzles 18.

An advantage of this second operating concept according to the invention consists in that at loads above the defined load limit (GW) the liquid fuel is not centrally introduced into the recirculation zone of the combustion chamber 1 but exclusively decentralized, so that for the entire introduced liquid fuel a homogeneous introduction to the combustion air and a part premixing with combustion air can be ensured as a result of which exhaust gas emissions, in particular nitrogen oxide emissions can be further reduced compared with the operating concept of FIG. 4. In particular, nitrogen oxide emissions of less than 90 vppm based on 15% oxygen can be realised

Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated, and in its operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. 

What is claimed is:
 1. A combustion chamber assembly of a gas turbine, for combusting a fuel in the presence of combustion air, the combustion chamber assembly comprising: a combustion chamber (1), in which combustion of fuel occurs, the combustion chamber (1) being delimited by a wall (2); a precombustion chamber (9), arranged upstream, in a fuel feeding direction, of the combustion chamber (1); an atomization device (4) configured to feed a liquid fuel to the precombustion chamber (9); and a swirl body (3) configured to feed combustion air and gaseous fuel to the precombustion chamber (9), wherein: the combustion chamber assembly is configured as a dual-fuel combustion chamber assembly, which, in a gas fuel operating mode, feeds a mixture of a gaseous fuel and combustion air to the combustion chamber (1) via the swirl body (3), and which, in a liquid fuel operating mode, feeds liquid fuel to the combustion chamber (1) via the atomization device (4) and combustion air to the combustion chamber (1) via the swirl body (3), and the atomization device (4) comprises: an atomization lance (17) with at least one atomization nozzle (15, 16), the atomization lance (17) being centrally arranged in the combustion chamber assembly with respect to a longitudinal center axis (20) of the combustion chamber assembly (1), and a plurality of atomization nozzles (18), the plurality of atomization nozzles (18) being arranged in the combustion chamber assembly in a decentralized manner with respect to the longitudinal center axis (20) of the combustion chamber assembly.
 2. The combustion chamber assembly according to claim 1, wherein the decentralized atomization nozzles (18) are arranged on a circular path (19) extending about the longitudinal center axis (20).
 3. The combustion chamber assembly according to claim 2, wherein a center point of the circular path (19), on which the decentralized atomization nozzles (18) are arranged, is positioned on the longitudinal center axis (20).
 4. The combustion chamber assembly according to claim 3, wherein the circular path (19), on which the decentralized atomization nozzles (18) are arranged, has a radius of between 0.4 times and 1.1 times an inner radius of the swirl body (3).
 5. The combustion chamber assembly according to claim 1, wherein: the centrally arranged atomization lance (17) comprises two atomization nozzles (15, 16) which, alone and jointly, provide an atomization cone (8 a) with a maximum spray angle (α) of 60° in each case, and each of the decentralized atomization nozzles (18) provides an atomization cone (8 b) with a maximum spray angle (β) of 50°.
 6. The combustion chamber assembly according to claim 1, wherein the centrally arranged atomization lance (17) is surrounded by an adjoining component (5) at least in sections, so as to form therebetween a radial gap (6) radially outside the centrally arranged atomization lance (17), the combustion chamber (1) being suppliable with combustion air via the radial gap (6) while bypassing the swirl body (3).
 7. The combustion chamber assembly according to claim 6, wherein the combustion air flow fed via the radial gap (6) comprises between 1% and 10% of the combustion air flow that is feedable to the combustion chamber (1) via the swirl body (3).
 8. The combustion chamber assembly according to claim 7, wherein the radial gap (6) is configured to supply the combustion chamber (1) with combustion air both in the gas fuel operating mode and in the liquid fuel operating mode.
 9. A gas turbine comprising: a combustion chamber assembly according to claim 1; and a turbine for expanding exhaust gas created during combustion in the combustion chamber assembly.
 10. A method for operating a gas turbine according to claim 9, comprising: supplying the combustion chamber (1) in the gas fuel operating mode with a mixture of a gaseous fuel and combustion air via the swirl body (3), and supplying the combustion chamber (1) in the liquid fuel operating mode with a liquid fuel via the atomization device (4) and combustion air at least via the swirl body (3).
 11. The method according to claim 10, wherein in the liquid fuel operating mode both the centrally arranged atomization lance (17) and the decentralized atomization nozzles (18) are utilized, throughout an operating range between a no load state and a full load state, to supply the combustion chamber (1) with the liquid fuel.
 12. The method according to claim 11, wherein via the centrally arranged atomization lance (17), throughout the operating range between the no load state and the full load state, a constant quantity of liquid fuel is supplied to the combustion chamber (1), and wherein power modulation is carried out by changing a quantity of the liquid fuel fed to the combustion chamber (1) via the decentralized atomization nozzles (18).
 13. The method according to claim 10, wherein in the liquid fuel operating mode, in an operating range below a predetermined load limit, both the centrally arranged atomization lance (17) and the decentralized atomization nozzles (18) are utilized to supply the liquid fuel to the combustion chamber (1), whereas in an operating range above the predetermined load limit the decentralized atomization nozzles are utilized (18) exclusively for supplying the liquid fuel to the combustion chamber (1).
 14. The method according to claim 13, wherein in the operating range below the predetermined load limit a constant quantity of liquid fuel is supplied via the centrally arranged atomization lance (17), wherein power modulation is carried out by changing a quantity of the liquid fuel supplied to the combustion chamber (1) via the decentralized atomization nozzles (18). 